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KohlerEngines.com
Troubleshooting
Do not attempt to service or replace major engine components, or any items that require special
timing or adjustment procedures. This work should be performed by a Kohler authorized dealer.
Possible Cause
Problem
No
Fuel
Improper
Fuel
Dirt In
Fuel
Line
Dirty
Debris
Screen
Incorrect
Oil Level
Engine
Overloaded
Dirty Air
Cleaner
Faulty
Spark
Plug
Will Not Start
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Hard Starting
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Stops Suddenly
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Lacks Power
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Operates Erratically
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Knocks or Pings
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Skips or Mis
fi
res
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Back
fi
res
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Overheats
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High Fuel
Consumption
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Engine Speci
fi
cations
Model
Bore
Stroke Displacement Oil Capacity
(Re
fi
ll)
Spark
Plug Gap
Maximum Angle
of Operation
(@ full oil level)*
CH621
3.03 in.
(77 mm)
2.6 in.
(67 mm)
38.1 cu. in.
(624 cc)
1.7-1.9 U.S. qt.
(1.6-1.8 L)
0.030 in.
(0.76 mm)
25°
CV621
CH641
CV641
CH620
3.2 in.
(80 mm)
41 cu. in.
(674 cc)
CV620
CH640
CV640
CH23/CH680
CH670
CV23/CV680
CV670
CH730
3.27 in.
(83 mm)
44.2 cu. in.
(725 cc)
CV730
CH740
CV740
CH750
2.72 in.
(69 mm)
45.6 cu. in.
(747 cc)
CV750
*Exceeding maximum angle of operation may cause engine damage from insuf
fi
cient lubrication.
Additional speci
fi
cation information can be found in service manual at KohlerEngines.com.
Exhaust Emission Control System for models CH23, CV23, CH620-CH740, CV620-CV740,
CH750, and CV750 is EM for U.S. EPA, California, and Europe.
Any and all horsepower (hp) references by Kohler are Certi
fi
ed Power Ratings and per SAE J1940
& J1995 hp standards. Details on Certi
fi
ed Power Ratings can be found at KohlerEngines.com.